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Photodynamic potential of hexadecafluoro zinc phthalocyanine in nanostructured lipid carriers: physicochemical characterization, drug delivery and antimicrobial effect against Candida albicans. Lasers Med Sci 2022; 37:3183-3191. [PMID: 35723829 DOI: 10.1007/s10103-022-03594-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 06/10/2022] [Indexed: 10/18/2022]
Abstract
This study aims to develop and characterize NCL loaded with ZnF16Pc (Pc) for application in antimicrobial photodynamic therapy. For the development of the NLC, the fusion-emulsification technique followed by sonication was applied. NLC and Pc-NLC were characterized in terms of mean diameter (Dm.n), polydispersity index (PdI), zeta potential (ZP), encapsulation efficiency (%EE), transmission electron microscopy (TEM), differential scanning (DSC), photobleaching and singlet oxygen generation in cellular systems (SOSG), and in vitro release assays performed by the beaker method, using dialysis membranes. Cell viability was performed by colony forming units (CFU/mL). The mean size of NLC and Pc-NLC was 158 nm ± 1.49 to 161.80 nm and showed PdI < 0.3 and ZP between -17.8 and -19.9, and stable during storage time (90 days). The TEM presented spherical particles, the Pc-NLC promoted the encapsulation of 75.57% ± 0.58. DSC analysis confirmed that there was no incompatibility between Pc and NLC. The analysis of the photodegradation profile proved to be photostable after encapsulation and this corroborates the data obtained by SOSG. In vitro release showed controlled and prolonged release. PDT Pc-NLC exhibited greater antifungal effect against C. albicans (3 log10 reduction) than Pc-NLC without light (1 log10 reduction). NLC can be an alternative to the application of Pc and improve the effect during PDT treatment.
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Guo L, Li YH, Fang S, Pan Y, Chen J, Meng YC. Characterization and interaction mechanism of selective protein separation by epsilon-polylysine: The role of hydrophobic attraction. Food Hydrocoll 2022. [DOI: 10.1016/j.foodhyd.2022.107710] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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3
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Clusters in colloidal dispersions with a short-range depletion attraction: Thermodynamic identification and morphology. J Colloid Interface Sci 2022; 618:442-450. [DOI: 10.1016/j.jcis.2022.03.061] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/10/2022] [Accepted: 03/14/2022] [Indexed: 11/19/2022]
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4
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Soto-Bustamante F, Valádez-Pérez NE, Castañeda-Priego R, Laurati M. Potential-invariant network structures in Asakura-Oosawa mixtures with very short attraction range. J Chem Phys 2021; 155:034903. [PMID: 34293895 DOI: 10.1063/5.0052273] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
We systematically investigated the structure and aggregate morphology of gel networks formed by colloid-polymer mixtures with a moderate colloid volume fraction and different values of the polymer-colloid size ratio, always in the limit of short-range attraction. Using the coordinates obtained from confocal microscopy experiments, we determined the radial, angular, and nearest-neighbor distribution functions together with the cluster radius of gyration as a function of size ratio and polymer concentration. The analysis of the structural correlations reveals that the network structure becomes increasingly less sensitive to the potential strength with the decreasing polymer-colloid size ratio. For the larger size ratios, compact clusters are formed at the onset of network formation and become progressively more branched and elongated with increasing polymer concentration/attraction strength. For the smallest size ratios, we observe that the aggregate structures forming the gel network are characterized by similar morphological parameters for different values of the size ratio and the polymer concentration, indicating a limited evolution of the gel structure with variations of the parameters that determine the interaction potential between colloids.
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Affiliation(s)
- Fernando Soto-Bustamante
- División de Ciencias e Ingenierías, Universidad de Guanajuato, Lomas del Bosque 103, 37150 León, Mexico
| | - Néstor E Valádez-Pérez
- Facultad de Ciencias en Física y Matemáticas, Universidad Autónoma de Chiapas, Carretera Emiliano Zapata km 8, 29050 Tuxtla Gutiérrez, Chiapas, Mexico
| | - Ramón Castañeda-Priego
- División de Ciencias e Ingenierías, Universidad de Guanajuato, Lomas del Bosque 103, 37150 León, Mexico
| | - Marco Laurati
- Dipartimento di Chimica and CSGI, Università di Firenze, 50019 Sesto Fiorentino, Italy
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Xu HN, Chu C, Wang L, Zhang L. Droplet clustering in cyclodextrin-based emulsions mediated by methylcellulose. SOFT MATTER 2019; 15:6842-6851. [PMID: 31406969 DOI: 10.1039/c9sm00875f] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Rapid droplet aggregation in cyclodextrin (CD)-stabilized emulsions limits their practical use as material templates. Herein, we formulate mixtures of submicron CD-based emulsion droplets suspended in aqueous solutions of methylcellulose (MC) with various concentrations and molecular weights. We evaluate the effects of MC on the microstructure and stability of the emulsions using different techniques including optical microscopy, laser particle analysis, confocal laser scanning microscopy and multiple light scattering, explore the rheological behavior of the emulsions through large amplitude oscillatory shear experiments, and study the viscoelastic nonlinearities of the emulsions as a function of strain and strain-rate space through nondimensional elastic and viscous Lissajous-Bowditch plots. It is demonstrated that the emulsion droplets are present in the form of small clusters and their size is almost independent of MC concentration and molecular weight. The clustering pattern is also supported by the changes in viscoelastic properties of the emulsions and the intracycle nonlinear behavior of the Lissajous-Bowditch plots. We propose for the first time that glass-like dynamic arrest takes place with the formation of small equilibrium droplet clusters in the situation where the CD-based emulsion droplets are forced by depletion flocculation and kinetic trapping simultaneously exerted by MC.
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Affiliation(s)
- Hua-Neng Xu
- State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Avenue, Wuxi, Jiangsu 214122, People's Republic of China.
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Niebuur BJ, Chiappisi L, Jung F, Zhang X, Schulte A, Papadakis CM. Kinetics of Mesoglobule Formation and Growth in Aqueous Poly(N-isopropylacrylamide) Solutions: Pressure Jumps at Low and at High Pressure. Macromolecules 2019. [DOI: 10.1021/acs.macromol.9b00937] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Bart-Jan Niebuur
- Physik-Department, Fachgebiet Physik weicher Materie, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany
| | - Leonardo Chiappisi
- Large Scale Structures Group, Institut Laue-Langevin, 71, Avenue des Martyrs, 38042 Grenoble, France
- Stranski Laboratorium für Physikalische und Theoretische Chemie, Institut für Chemie, Technische Universität Berlin, Straße des 17. Juni 124, Sekr. TC7, D-10623 Berlin, Germany
| | - Florian Jung
- Physik-Department, Fachgebiet Physik weicher Materie, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany
| | - Xiaohan Zhang
- Physik-Department, Fachgebiet Physik weicher Materie, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany
| | - Alfons Schulte
- Department of Physics and College of Optics and Photonics, University of Central Florida, 4111 Libra Drive, Orlando, Florida 32816-2385, United States
| | - Christine M. Papadakis
- Physik-Department, Fachgebiet Physik weicher Materie, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany
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7
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Valadez-Pérez NE, Liu Y, Castañeda-Priego R. Reversible Aggregation and Colloidal Cluster Morphology: The Importance of the Extended Law of Corresponding States. PHYSICAL REVIEW LETTERS 2018; 120:248004. [PMID: 29956967 DOI: 10.1103/physrevlett.120.248004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 12/14/2017] [Indexed: 06/08/2023]
Abstract
Cluster morphology of spherical particles interacting with a short-range attraction has been extensively studied due to its relevance to many applications, such as the large-scale structure in amorphous materials, phase separation, protein aggregation, and organelle formation in cells. Although it was widely accepted that the range of the attraction solely controls the fractal dimension of clusters, recent experimental results challenged this concept by also showing the importance of the strength of attraction. Using Monte Carlo simulations, we conclusively demonstrate that it is possible to reduce the dependence of the cluster morphology to a single variable, namely, the reduced second virial coefficient, B_{2}^{*}, linking the local properties of colloidal systems to the extended law of corresponding states. Furthermore, the cluster size distribution exhibits two well-defined regimes: one identified for small clusters, whose fractal dimension, d_{f}, does not depend on the details of the attraction, i.e., small clusters have the same d_{f}, and another related to large clusters, whose morphology depends exclusively on B_{2}^{*}, i.e., d_{f} of large aggregates follows a master curve, which is only a function of B_{2}^{*}. This physical scenario is confirmed with the reanalysis of experimental results on colloidal-polymer mixtures.
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Affiliation(s)
- Néstor E Valadez-Pérez
- División de Ciencias e Ingenierías, Campus León, Universidad de Guanajuato, Loma del Bosque 103, 37150 León, Guanajuato, Mexico
- Department of Chemical and Biological Engineering, Illinois Institute of Technology, 3440 S. Dearborn Street, Chicago, Illinois 60616, USA
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
| | - Yun Liu
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware 19716, USA
| | - Ramón Castañeda-Priego
- División de Ciencias e Ingenierías, Campus León, Universidad de Guanajuato, Loma del Bosque 103, 37150 León, Guanajuato, Mexico
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
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Das S, Riest J, Winkler RG, Gompper G, Dhont JKG, Nägele G. Clustering and dynamics of particles in dispersions with competing interactions: theory and simulation. SOFT MATTER 2017; 14:92-103. [PMID: 29199754 DOI: 10.1039/c7sm02019h] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Dispersions of particles with short-range attractive and long-range repulsive interactions exhibit rich equilibrium microstructures and a complex phase behavior. We present theoretical and simulation results for structural and, in particular, short-time diffusion properties of a colloidal model system with such interactions, both in the dispersed-fluid and equilibrium-cluster phase regions. The particle interactions are described by a generalized Lennard-Jones-Yukawa pair potential. For the theoretical-analytical description, we apply the hybrid Beenakker-Mazur pairwise additivity (BM-PA) scheme. The static structure factor input to this scheme is calculated self-consistently using the Zerah-Hansen integral equation theory approach. In the simulations, a hybrid simulation method is adopted, combing molecular dynamics simulations of colloids with the multiparticle collision dynamics approach for the fluid, which fully captures hydrodynamic interactions. The comparison of our theoretical and simulation results confirms the high accuracy of the BM-PA scheme for dispersed-fluid phase systems. For particle attraction strengths exceeding a critical value, our simulations yield an equilibrium cluster phase. Calculations of the mean lifetime of the appearing clusters and the comparison with the analytical prediction of the dissociation time of an isolated particle pair reveal quantitative differences pointing to the importance of many-particle hydrodynamic interactions for the cluster dynamics. The cluster lifetime in the equilibrium-cluster phase increases far stronger with increasing attraction strength than that in the dispersed-fluid phase. Moreover, significant changes in the cluster shapes are observed in the course of time. Hence, an equilibrium-cluster dispersion cannot be treated dynamically as a system of permanent rigid bodies.
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Affiliation(s)
- Shibananda Das
- Theoretical Soft Matter and Biophysics, Institute for Advanced Simulation and Institute of Complex Systems, Forschungszentrum Jülich, 52425 Jülich, Germany.
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Affiliation(s)
- M. B. Sweatman
- School of Engineering, University of Edinburgh , Edinburgh, UK
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10
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Kalyuzhnyi YV, Jamnik A, Cummings PT. Melting upon cooling and freezing upon heating: fluid-solid phase diagram for Švejk-Hašek model of dimerizing hard spheres. SOFT MATTER 2017; 13:1156-1160. [PMID: 28097283 DOI: 10.1039/c6sm02572b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A simple model of dimerizing hard spheres with highly nontrivial fluid-solid phase behavior is proposed and studied using the recently proposed resummed thermodynamic perturbation theory for central force (RTPT-CF) associating potentials. The phase diagram has the fluid branch of the fluid-solid coexistence curve located at temperatures lower than those of the solid branch. This unusual behavior is related to the strong dependence of the system excluded volume on the temperature, which for the model at hand decreases with increasing temperature. This effect can be also seen for a wide family of fluid models with an effective interaction that combines short range attraction and repulsion at a larger distance. We expect that for sufficiently high repulsive barrier, such systems may show similar phase behavior.
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Affiliation(s)
- Yurij V Kalyuzhnyi
- Institute for Condensed Matter Physics of the National Academy of Sciences of Ukraine, 1 Svientsitskii St., Lviv, 79011, Ukraine.
| | - Andrej Jamnik
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 113, 1000 Ljubljana, Slovenia.
| | - Peter T Cummings
- Department of Chemical and Biochemical Engineering, Vanderbilt University, Nashville, TN 37235-1604, USA.
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11
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Shielded attractive shell model of polymerizing hard spheres of different size. Resummed thermodynamic perturbation theory and computer simulation. J Mol Liq 2017. [DOI: 10.1016/j.molliq.2016.09.121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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12
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Ahila N, Ramkumar VS, Prakash S, Manikandan B, Ravindran J, Dhanalakshmi P, Kannapiran E. Synthesis of stable nanosilver particles (AgNPs) by the proteins of seagrass Syringodium isoetifolium and its biomedicinal properties. Biomed Pharmacother 2016; 84:60-70. [DOI: 10.1016/j.biopha.2016.09.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Revised: 08/29/2016] [Accepted: 09/01/2016] [Indexed: 01/31/2023] Open
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13
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Riest J, Nägele G. Short-time dynamics in dispersions with competing short-range attraction and long-range repulsion. SOFT MATTER 2015; 11:9273-9280. [PMID: 26426932 DOI: 10.1039/c5sm02099a] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Dynamic clustering of globular Brownian particles in dispersions exhibiting competing short-range attraction and long-range repulsion (SALR) such as low-salinity protein solutions has gained a lot of interest over the past few years. While the structure of the various cluster phases has been intensely explored, little is known about the dynamics of SALR systems. We present the first systematic theoretical study of short-time diffusion and rheological transport properties of two-Yukawa potential SALR systems in the single-particle dominated dispersed-fluid phase, using semi-analytic methods where the salient hydrodynamic interactions are accounted for. We show that the dynamics has unusual features compared to reference systems with pure repulsion or attraction. Results are discussed for the hydrodynamic function characterizing short-time diffusion that reveals an intermediate-range-order (cluster) peak, self-diffusion and sedimentation coefficients, and high-frequency viscosity. As important applications, we discuss the applicability of two generalized Stokes-Einstein relations, and assess the wavenumber range required for the determination of self-diffusion in a dynamic scattering experiment.
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Affiliation(s)
- Jonas Riest
- Forschungszentrum Jülich GmbH, ICS-3 - Soft Condensed Matter, 52425 Jülich, Germany. and Jülich-Aachen Research Alliance JARA - Soft Matter, 52425 Jülich, Germany
| | - Gerhard Nägele
- Forschungszentrum Jülich GmbH, ICS-3 - Soft Condensed Matter, 52425 Jülich, Germany. and Jülich-Aachen Research Alliance JARA - Soft Matter, 52425 Jülich, Germany
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14
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Henry C, Norrfors KK, Olejnik M, Bouby M, Luetzenkirchen J, Wold S, Minier JP. A refined algorithm to simulate latex colloid agglomeration at high ionic strength. ADSORPTION 2015. [DOI: 10.1007/s10450-015-9714-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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15
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Khoshniyat A, Sharif A, Aalaie J. Experimental and thermodynamic investigation of the stability of copolymer grafted bentonite nanoclays in a high salinity electrolyte. POLYMER SCIENCE SERIES A 2015. [DOI: 10.1134/s0965545x1507007x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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16
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Koroleva M, Tokarev A, Yurtov E. Simulation of flocculation in W/O emulsions and experimental study. Colloids Surf A Physicochem Eng Asp 2015. [DOI: 10.1016/j.colsurfa.2015.05.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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17
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Kim S, Hyun K, Moon JY, Clasen C, Ahn KH. Depletion stabilization in nanoparticle-polymer suspensions: multi-length-scale analysis of microstructure. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:1892-1900. [PMID: 25611871 DOI: 10.1021/la504578x] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We study the mechanism of depletion stabilization and the resultant microstructure of aqueous suspensions of nanosized silica and poly(vinyl alcohol) (PVA). Rheology, small-angle light scattering (SALS), and small-angle X-ray scattering (SAXS) techniques enable us to analyze the microstructure at broad length scale from single particle size to the size of a cluster of aggregated particles. As PVA concentration increases, the microstructure evolves from bridging flocculation, steric stabilization, depletion flocculation to depletion stabilization. To our surprise, when depletion stabilization occurs, the suspension shows the stabilization at the cluster length scale, while maintaining fractal aggregates at the particle length scale. This sharply contrasts previously reported studies on the depletion stabilization of microsized particle and polymer suspensions, which exhibits the stabilization at the particle length scale. On the basis of the evaluation of depletion interaction, we propose that the depletion energy barrier exists between clusters rather than particles due to the comparable size of silica particle and the radius gyration of PVA.
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Affiliation(s)
- Sunhyung Kim
- Department of Chemical Engineering, KU Leuven, University of Leuven , W. de Croylaan 46, B-3001 Heverlee, Belgium
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18
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Meng X, Wu H, Morbidelli M. Snapshotted glass and gel transitions of stable colloidal dispersions after shear-driven aggregation in a microchannel. SOFT MATTER 2015; 11:981-986. [PMID: 25519211 DOI: 10.1039/c4sm01339e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Intense shear can lead to aggregation of colloids that are highly stable at rest. The aggregation process typically has an induction time, and then becomes explosive, leading to rapid phase transitions. We study the phase evolution during shear-driven aggregation in a short microchannel (MC) under intense shear for a colloid with a high interaction energy barrier that ensures high stability of particles and clusters before and after intense shear. The short residence time allows us to snapshot the phase evolution by repeatedly cycling the colloid in the MC. It is found that, depending on the particle concentration, in addition to a fluid of clusters and a solid-like gel, there is another solid-like state between them: Wigner glass of clusters. Their transitions occur over a large range of particle concentrations. We have proposed a phase diagram that describes how the transitions of the three phases evolve in the aggregation steady state in the colloidal interaction vs. particle concentration plane.
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Affiliation(s)
- Xia Meng
- Institute for Chemistry and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, 8093 Zurich, Switzerland.
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19
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Evdokimov IN, Losev AP. Settling Properties and Fractal Dimensions of Aggregated Water Emulsions in Native Crude Oils. J DISPER SCI TECHNOL 2015. [DOI: 10.1080/01932691.2013.783493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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20
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Chinchalikar AJ, Aswal VK, Kohlbrecher J, Wagh AG. Small-angle neutron scattering study of structure and interaction during salt-induced liquid-liquid phase transition in protein solutions. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2013; 87:062708. [PMID: 23848716 DOI: 10.1103/physreve.87.062708] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2013] [Indexed: 06/02/2023]
Abstract
The liquid-liquid phase transition (LLPT) in aqueous salt solutions of lysozyme protein has been studied by small-angle neutron scattering. Measurements have been carried out on fixed protein concentration with varying salt concentration approaching LLPT. The data are fitted considering protein interaction by the two Yukawa (2Y) potential which combines short-range attraction and long-range repulsion. We show that LLPT arises because of enhancement of non-DLVO (Derjaguin-Landau-Verwey-Overbeek) short-range attraction without any conformational structural change of the protein. The salt concentration required for LLPT as well as corresponding short-range attraction decreases significantly with increase in protein concentration.
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Affiliation(s)
- A J Chinchalikar
- Solid State Physics Division, Bhabha Atomic Research Centre, Mumbai-400085, India
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Chronopoulou L, Cutonilli A, Cametti C, Dentini M, Palocci C. PLGA-based nanoparticles: effect of chitosan in the aggregate stabilization. A dielectric relaxation spectroscopy study. Colloids Surf B Biointerfaces 2012; 97:117-23. [PMID: 22609591 DOI: 10.1016/j.colsurfb.2012.04.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2012] [Revised: 04/10/2012] [Accepted: 04/12/2012] [Indexed: 11/18/2022]
Abstract
Chitosan-modified polylactic-co-glycolic acid (PLGA) nanoparticles with average diameter of 200 nm in PBS buffer solution have been investigated by means of dielectric relaxation spectroscopy measurements in the frequency range (1 MHz-2 GHz) where interfacial polarizations occur. PLGA-based nanoparticles offer remarkable advantages in different biotechnological fields, such as their biocompatibility, easiness of administration and rather complete biodegradation. However, despite the use of these drug delivery systems is increasing, little is known about the basic process involved in the formation of complexes and in the subsequent release kinetics. In the present work, we have characterized the colloidal behavior of PLGA-based nanoparticles in the presence of oppositely charged chitosan polyelectrolyte by means of dynamic light scattering, electrophoretic mobility and radiowave dielectric relaxation measurements. In particular, we have emphasized how the presence of a coating layer at the nanoparticle surface could exert a marked slowing-down in the drug release. The consequence of this finding is briefly discussed at the light of some biological implications.
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Affiliation(s)
- L Chronopoulou
- Department of Chemistry, University of Rome La Sapienza, Rome, Italy
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22
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Khoshniyat A, Hashemi A, Sharif A, Aalaie J, Duobis C. Effect of surface modification of bentonite nanoclay with polymers on its stability in an electrolyte solution. POLYMER SCIENCE SERIES B 2012. [DOI: 10.1134/s1560090412010034] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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23
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Odriozola G. Ion-specific colloidal aggregation: Population balance equations and potential of mean force. J Chem Phys 2011; 135:134704. [DOI: 10.1063/1.3644769] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
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Fritzsche A, Rennert T, Totsche KU. Arsenic strongly associates with ferrihydrite colloids formed in a soil effluent. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2011; 159:1398-1405. [PMID: 21310516 DOI: 10.1016/j.envpol.2011.01.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2010] [Revised: 12/22/2010] [Accepted: 01/03/2011] [Indexed: 05/30/2023]
Abstract
Arsenic mobility may increase in liquid phase due to association with colloidal Fe oxides. We studied the association of As with Fe oxide colloids in the effluent from water-saturated soil columns run under anoxic conditions. Upon exfiltration, the solutions, which contained Fe2+, were re-aerated and ferrihydrite colloids precipitated. The entire amount of effluent As was associated with the ferrihydrite colloids, although PO4(3-), SiO4(4-), CO3(2-) and dissolved organic matter were present in the effluent during ferrihydrite colloid formation. Furthermore, no subsequent release of As from the ferrihydrite colloids was observed despite the presence of these (in)organic species known to compete with As for adsorption on Fe oxides. Arsenic was bound via inner-sphere complexation on the ferrihydrite surface. FTIR spectroscopy also revealed adsorption of PO4(3-) and polymerized silica. However, these species could not impede the quantitative association of As with colloidal ferrihydrite in the soil effluents.
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Affiliation(s)
- Andreas Fritzsche
- LS Hydrogeologie, Institut für Geowissenschaften, Friedrich-Schiller-Universität Jena, Burgweg 11, D-07749 Jena, Germany.
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25
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Synthesis structure and stability of amino functionalized PEGylated silica nanoparticles. Colloids Surf A Physicochem Eng Asp 2010. [DOI: 10.1016/j.colsurfa.2010.05.036] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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26
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Kovalchuk NM, Kuchin I, Starov V, Uriev N. Aggregation in colloidal suspensions and its influence on the suspension viscosity. COLLOID JOURNAL 2010. [DOI: 10.1134/s1061933x10030117] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Cerbelaud M, Ferrando R, Videcoq A. Simulations of heteroaggregation in a suspension of alumina and silica particles: Effect of dilution. J Chem Phys 2010; 132:084701. [DOI: 10.1063/1.3328876] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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